The first execution in Indonesia in more than four years is a shocking and regressive step, Amnesty International said as it urged the government to not follow through on promises to put a further nine people to death in 2013.

Last night, Adami Wilson, a 48-year old Malawian national who was convicted for drug trafficking in 2004, was executed by firing squad in Jakarta. It was the first execution in Indonesia since November 2008.

The Indonesian Attorney General Basrief Arief said that the authorities planned to put at least a further nine death row inmates to death in 2013.

"This is really outrageous news. We oppose the death penalty in all circumstances, but Indonesia's long period without executions and the pledge to put even more people to death, makes this even more shocking," said Papang Hidayat, Amnesty International's Indonesia Researcher.

Wilson was first convicted for trafficking 1 kg of heroin in 2004 in Tangerang, south-western Banten province.

Yesterday's execution is the first in Indonesia in more than four years. The previous one happened on 9 November 2008, when three of the men involved in the 2002 Bali bombings were put to death.

After Wilson was executed by firing squad, the Attorney General today said that at least nine more executions would be carried out this year, and that as many as 20 death row inmates could be executed.

Around 130 people are believed to be on death row in Indonesia – more than half of them have been convicted of drug trafficking. Many are foreign nationals. The use of the death penalty for drug-related offences does not meet the threshold of the "most serious crimes" as prescribed under international law.

"This is an incomprehensible statement from the Attorney General – carrying out even more executions now would be hugely regressive. We urge the Indonesia government to immediately halt any plans to put more people to death," Hidayat said.

Today's events are at odds with positive indications that Indonesia was moving away from the death penalty.

In October 2012, after President Susilo Bambang Yudhoyono commuted the death sentence of a drug trafficker, Foreign Minister Marty Natalegawa said the move was part of a wider push away from the use of the death penalty in Indonesia.

At the UN General Assembly in December 2012, Indonesia for the first time abstained from voting against a resolution calling for a global moratorium on the death penalty.

"What makes this so disappointing is that we have really seen the Indonesian government sending progressive signals on moving away from the death penalty in recent years," Hidayat said.

"The last year has seen many other countries in the region, including Malaysia and Singapore, taking steps to limit the use of the death penalty, including for drug-related offences. We expected Indonesia to be leading this trend – not dragging the region backwards."